"Storms will move through the world and can bring disaster for those unprepared. They leave destruction and death in their wake when they have moved on. In those times I am pulled to collect the fallen. A similar thing happens when you move on as well."

Then Death would again come in to collect the fallen. So to liken Matthias to a storm was rather accurate. Perhaps not quite to the level of a natural disaster but a storm was simple enough. A few possible deaths that would require his attention and nothing more.